Engine starter gearing



Dec. 9, 1941. B w JONES 2,265,374

ENGINE STARTER GEARING Filed Ap'rl 30, 1940 2 Sheets-Sheet l BY 3M/TM c/wws Dec. 9, 1941.` B. w. JONES ENGINE STARTER GEARING Filed April 50,1940

2 Sheets-Sheet 2 INVENTOR. BY Gm/0. @/orws MAIER Patented Dec. 9, 194i ENGINE STARTER GEARING Burr W. Jones, Elmira Heights, N. Y., assignor to Bendix Aviation Corporation, South Bend, Ind., a corporation of Delaware Application April 30, 1940, Serial No. 332,531

'Ihe present invention relates to engine starter gearing and more particularly to a device for manually controlling the connection of a starting motor with a member of an engine to be started.

Manually controlled starter gearing commonly comprises a pinion rotatable from a starting motor and movable axially into and out of mesh with an engine gear by shifting means which may be operated by manually or magnetically actuated linkages. In starters of this type, some form vof overrunning connection between the pinion and starting motor is usually provided to prevent the starting motor from being rotated at excessive speed when the engine starts, prior to withdrawal of the pinion from the engine gear. In some devices of this character, instead of utilizing an overrunning clutch, certain forms of speed-controlled devices have been used to withdraw the pinion upon rotation thereof at eXcessive speeds. These devices, however, have the disadvantage that demeshing of the pinion may occur before a true start of the engine is secured, and it then becomes necessary to re-engage the pinion with the engine gear in order to resume cranking. If the operator permits this action to take place automatically by maintaining the linkage in operative position, severe milling of the pinion teeth against the teeth of the engine gear may take place.

It is an object of the present invention to provide a novel manual shift for starter gears in which the starting pinion is moved manually into driving position but may be returned to idle position by automatic means dependent on the speed of rotation of the starting motor.

It is another object to provide such a device in which the manual shifting means includes spring members adapted to yield in case of tooth abut* ment of the pinion and engine gear, and thereafter snap the pinion into mesh with an engine gear.

It is another object to provide such a device in which the spring members are arranged to be deflected by centrifugal force so as to withdraw the pinion from mesh when the starting motor has attained a predetermined speed of rotation.

It is another object to provide such a device in which an overrunning clutch is interposed between the centrifugal controlling device and the pinion whereby the centrifugal device is independent of the speed of rotation of the pinion.

It. is another object to provide such a device inwhich the overrunning clutch is controlled by gij,

the shifting Ameans so as to .be closed. by the 55 meshing action of the shifting means by the demeshing action thereof.

It is a further object to provide such a device in which the shifting means is arranged to be re-eniorced after initial mesh of the pinion is secured so as to afford a substantially positive control of the pinion and overrunning clutch.

Further objects and advantages will be apparent from the following description taken in connection with the accompanying drawings in which:

Fig.' l is a side elevation partly in section oi' starter gearing embodying a preferred form of the invention, the parts being shown in idle position;

Fig. 2 is a similar view showing the parts in cranking position;

lFig. 3 is a similar View showing the parts in the positions assumed after the engine starts but before the shifting mechanism is returned to idle position;

Fig. 4 is a similar view showing the parts in the positions assumed during the meshing operation when a tooth of the pinion abuts against a tooth of the engine gear;

Fig. 5 is a detail in perspective and partly in section of the members of the overrunning clutch shown in disassembled relation;

Fig. 6 is a detail in perspective of the shift collar;

Fig. 7 is a section taken substantially on the line 'l-'l of Fig. 1; and

Fig. 8 is an end view from the right of the drive illustrated in Fig. 1.

In Fig. l of the drawings there is illustrated a power shaft I which may be the extended armature shaft of a starting motor, not illustrated. A sleeve 2 is iixedly mounted thereon as by means of a double-D section 3 formed on the end of the power shaft and a bore 4 conforming thereto in the end of the sleeve, a split lock ring 5 seated in a groove on the end of the power shaft being provided to maintain the sleeve against longitudinal movement.

A driving clutch member 6 is splined on the sleeve 2 as by means of inwardly extending lugs 'l which slidably engage in slots 8 of the sleeve. A shift collar 9 is slidably journalled on the sleeve 2, normally resting against a shoulder I l formed on the end of said sleeve. Means for imparting longitudinal movement from the shift collar to the driving clutch member 6 is provided in the form of a plurality of fiat spring members I2v plvoted at their ends as indicated at I3 and I4 to the shift collar and driving clutch member and opened respectively in such manner as to form in eect a yielding toggle connection therebetween. Weight members I are mounted rigidly on the springs I2 intermediate their ends at points corresponding to the hinges of the toggles formed by the springs. Weights I5 bow out the springs by resting on the surface of sleeve 2 when the parts are in idle position as shown in Fig. 1, and further bow out the springs I2 to withdraw the pinion froml mesh under the action of centrifugal force when the shift collar and clutch member are rotating above a predetermined minimum speed. The natural set of the springs I2 is inward toward the axis of the drive so thatthe weight members I5 are ordinarily mressednin# ward with suilcient force to resist-'the ao'tionof -A centrifugal force at speeds below the predetermined minimum. I

A pinion I6 is slidably journalled on the power shaft I for axial movement into and outof engagement with a member-such as a .gear I'I -of an engine to be started( uA barrel member IB is rigidly connected to the-.end-of the pinion in any suitable mannen'and a driven clutch'mmberlg is xed the barrel as by means of'radial'lugs thereof. The longitudinal motion of the driving clutch member 6 is transmitted through the spring to the driven clutch member I9 and from thence through the barrel I8 to the pinion I6 to move it into engagement with the gear I1. If the teeth of the pinion I6 enter properly in the tooth spaces of the gear I1, this longitudinal motion continues until the driven clutch member I9 engages the stop ring 2?,'at which time the pinion'is fully meshed with the yengine gear. As soon as the parts have been shifted sufciently to permit the weight members I5 to ride down the'inclines 29 of the sleeve 2 and bear against the power shaft I, the springs I2 become re-enyforced bythe bracing action of the weight mem- -be1s against the power shaft so that when the Y' driven clutch member I9 engages the stop 21, further pressure ofy the shift collar 9 causes the 2l engaging .iny slots 22 of the'barr'el. Clutch' members vIi and fig are provided with'tee'th '23 and 24 respectivelyrwhich are adapted to engage and transmit rotation from the driving clutch member-.5 to the driven clutch member I9,V but which are beveled o'i as best seen in Fig. 5 in such a manner as to disengage when the driven clutch member overruns the driving clutch member. A spring 425 is interposed between the clutch members in order to normally maintain them out of engagement. Y Y I Driving clutch member S is maintained in the end of the `barrel VIibysuitable means suchA Aas a split lockrin'g25.` Means for defining the operativeY position of the pinionv and its associated parts is provided in the formof a stop ring 21 seated on ,the inner end of the sleeve V2 against alock ring 28. Y Y Y t SlotsV 8 of the sleeve l-2 are terminated `by in, clined shoulders 29 which are ynormally located a short distance away from and inaXial alignment V withthe positions .assumed by the weight members I5 when the par-tsvare in their .idle positions. Weight members I5 are formed to enter slots 8 by impulsion of the inward set of springs I2y when the weights are broughtv into registry with the slots bylongitudinal `'movement of the-shift'collar 9 to thesleft. When -the weight members thus enter the slots -fthe springs I2 ileX inwardly past their straight .orl'dead-center positions fto the Ypositions illustrated in Fig. u2.

When so flexed, the springs .are rie-enforced or stiiened by the bearingrof ,the yweight members against the power shaft I inasmuch as longitudinalvcompression of the springs I2 then tendsto bend the springs inwardly rather than outwardly asis the ca se'when -the parts arein idle position. The lsprings I2 thus becomesubstantially rigid in their transmission of longitudinal lmotion .from

the shift vcollar to the driving clutch member 6 for closing the clutch after the the slots 8. Y

In operation, `starting with'theparts in thepo-V sitionsillustrated in Fig. l, motion Vof theshift collar ,9 tothe left byA anyyform of manually or magnetically operatedflinkage, not/illustrated, is

weights I5 enter transmitted yieldingly by the springs. I2 to the*Y driving clutch vmember 6 since at this time the springs are bowed youtwardly and longitudinal pressure tends to increase. the `V`outward v fiexureV 'spring 25 to'yield and the teeth 23 of the drivingolutch member 5 to engage with the teeth 24.01 lthe driven clutch member I9. Y i

TheY starting motor being nowenergized vin any suitable manner, rotation ofthe powershaft I thereby .is transmitted nfrom the sleeve 2 through clutch members 6 and I9 and barrel'l to the pinion-I5 to Vcrank4 the engine. `When the engine starts, the driven lclutch member I9 overruns-the driving clutchv member 5 so that the acceleration of the pinion I6 by the engine gear is not transmitted back to the .starting motor. If the operator releases the shifting mechanism, the parts are returned .to idle position by the usual return spring .of the linkage. If, however, the operator does not-so release Vthe shifting mechanism andthereby Yopen the switch of the star-ting motor, the motorwifll rotate at *high speed, thus rotating theV shifting Vmechanism whereby the weights L5 move Vout yas shown in Fig. A3, withdrawing the pinion v.and its vassociated parts yback to their idle positions .althoughrthe shift icollar 'B is maintained in ,operative position. When. the operator-.thereafter releases the flinkage, .the :shift collar returns @to its idle-position f ting the 'shift collar to -move suciently to Aallow' the starting switchtobe closed. Asjso'onzas initial rotation of the powers'ha'ftby 'the'starting motor "takes place, the'tteeth of the pinion are indexedintojproper registry` Withthe tooth spaces ofthe engine gear and the ,springs 12 contract and Vsnap Vthe pinion into .mesh with the .engine gear, `whereupon meshing rand cranking take place as usual. l Although butone embodiment of vthe invention has `been `sho'wnand described in detail, it Ywilllbe understood .that other .embodimentsV are possible and various changes may be made in the design andarrangement of the parts Awitlioutgdeparting from .the spiritof the invention as v,dei-ined inthe claims appended hereto. Whatrisclaimed is: l. Engine rstarter gearing including apower. shaft, a pinion :slidably journalled thereon.. a sleeve-fixed. onthe shaft, a drivenr clutchmember non-`rotatably connected Tto ith'e ip'inion, fa' driving clutch :member slidablymounted Aon :the sleeve and/connected Vto :rotate therewith, arv shift collar slidably mounted on :the sleeve, yieldingr means connecting. the shift fcollar to .the driving. clutch, and means dresponsive to :rotation :sofgithe .power shaft above a predetermined speed for contracting said yielding means.

2. Engine starter gearing including a power shaft, a pinion slidably journalled thereon for movement into and out of engagement with a member of an engine to be started, a sleeve fixed on the shaft, a driven clutch member non-rotatably connected to the pinion, a driving clutch member splined on the sleeve, a shift collar slidably mounted on the sleeve, yielding means connecting the shift collar to the driving clutch, and means responsive to rotation of the power shaft above a predetermined speed for moving the pinion to idle position.

3. Engine starter gearing including a power shaft, a pinion slidably journalled thereon for movement into and out of engagement with a member of an engine to be started, a sleeve fixed on the shaft, a driven clutch member non-rotatably connected to the pinion, a driving clutch member splined on the sleeve, a shift collar slidably mounted on the sleeve, means connecting the collar to the driving clutch member adapted to yield compressively, and a centrifugal member rotatable with the connecting means for collapsing the connecting means to withdraw the pinion to idle position.

4. In engine starter gearing, a pinion, means including an overrunning clutch for rotating the pinion, manually operable means for moving the pinion into and out of engagement with a member of an engine to be started including a spring adapted to yield in case of tooth abutment between the pinion and engine member, and means for re-enforcing the spring after initial mesh of the pinion is secured.

5. In engine starter gearing, a pinion, means including an overrunning clutch for rotating the pinion, manually operable means for moving the pinion into and out of engagement with a member of an engine to be started including a toggle device arranged to yield in case of tooth abutment between the pinion and engine member, and means for bracing the toggle to stiffen it against endwise compression after the pinion is initially meshed with the engine member.

6. In engine starter gearing, a pinion, means including an overrunning clutch for rotating the pinion, manually operable means for moving the pinion into and out of engagement with a member of an engine to be started including a toggle device arranged to yield in case of tooth abutment between the pinion and engine member, supporting means for the central portion of the toggle, and means for flexing the toggle beyond its dead-center position and into engagement with said supporting means after initial mesh of the pinion with the engine member.

"1. Engine starter gearing including a pinion movable axially into and out of mesh with a member of an engine to be started, means for rotating the pinion including an overrunning clutch having a slidably mounted driving member and a driven member connected to rotate the pinion, and manually operable means for transmitting longitudinal movement through the driving and driven clutch members to the pinion, said transmitting means including an elastic element arranged to yield in case of tooth abutment between the pinion and engine member, and centrifugal means for collapsing the elastic element.

8. Engine starter gearing including a pinion movable axially into and out of mesh with a member of an engine to be started, means for rotating the pinion including an overrunning clutch having a slidably mounted driving memer and a driven member connected to rotate the pinion, and manually operable means for transmitting longitudinal movement through the driving and driven clutch members to the pinion, said transmitting means including an elastic element arranged to yield in case of tooth abutment between the pinion and engine member, and means for stiifening the elastic element after the pinion is initially engaged with the engine member.

9. In engine starter gearing, a power shaft, a pinion slidably journalled thereon for axial movement into engagement with an engine gear, a sleeve xed on the power shaft, and means for moving the pinion into mesh with the engine gear and for driving the pinion from the sleeve including a driven clutch member non-rotatably connected to the pinion, a driving clutch member splined on the sleeve, a manually operable shift collar, and a spring member connecting the shift collar and driving `clutch member, said spring member being provided with a centrifugal weight element intermediate its length.

10. In engine starter gearing, a power shaft, a pinion slidably journalled thereon for axial movement into engagement with an engine gear, a sleeve fixed on the power shaft, and means for moving the pinion into mesh with the engine gear and for driving the pinion from the sleeve including a driven clutch member non-rotatably connected to the pinion, a driving clutch member splined on the sleeve, a manually operable shift collar, and a spring member connecting the shift collar and driving clutch member, said spring member being at and being normally bowed outward but being permitted to bend in and obtain support for its mid-portion from the power shaft after initial mesh of the pinion with the engine gear.

11. In engine starter gearing, a power shaft, a pinion slidably journalled thereon for axial movement into engagement with an engine gear, a sleeve fixed on the power shaft, means for moving the pinion into mesh with the engine gear and for driving the pinion from the sleeve including a driven clutch member non-rotatably connected to the pinion, a driving clutch member splined on the sleeve, a manually operable shift collar, and a spring member connecting the shift collar and driving clutch member, said spring member being flat and so set as to have a natural deflection inward toward the axis of the drive, and means for bowing said spring outward away from said axis when the parts are in idle position, said means being arranged to allow the spring to bend inward and obtain support for its mid-portion from the power shaft after the parts are so moved as to obtain initial mesh of the pinion with the engine gear.

BURR W. JONES. 

